Fan assembly

ABSTRACT

A fan assembly includes a radiator, a fan, a shielding device and a guard device. The shielding device has at least a fixing part so that the shielding device can be attached to the radiator. The guard device is disposed on the shielding device and is formed with hard skeleton with several openings to surround the fan so that fluid can enter the radiator via the openings. Hence, the openings of the guard device can increase flow rate of the fluid entering the radiator, decrease noise and prevent the fan from being offended by foreign objects.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a fan assembly, and particularly to a fan frame of a cooling fan.

2. Description of Related Art

Due to increase of heat generated from electronic parts and reduction of sizes thereof, the density of generated heat becomes increasing quickly. As a result, performance and reliability of the product will be influenced if heat dissipation is not effectively provided and even the life span thereof will be shortened. Hence, how to discharge the increasing heat effectively is a great challenge to research personnel of related fields.

It is predictable that various electronic parts such as integrated transistors like integrated circuits (IC) will be getting more with the number thereof and function thereof will become more complete. Thus, the problem of heat dissipation during the electronic parts running will become a obstacle has to be considered.

Currently, the computer is a typical application with regard to heat generation. In order to reduce high temperature resulting from operation of the central processing unit, heat dissipation device associated with a fan is used generally. The design concept is that the heat dissipation device made of metal with high conduction coefficient such as copper or aluminum adheres the surface of an electronic part tightly so that heat generated from the electronic part can dissipate by way of conduction and convention of the fan blowing. Hence, the electronic part can operate at a constant working temperature. It is known that heat conduction rate of the heat dissipation device depends on the heat dissipation area, that is, a big heat dissipation area provides better heat dissipation effect and a small heat dissipation area provides less heat dissipation effect. However, the heat dissipation device in a narrow space of the computer main unit can only have a very limited size. Therefore, how to increase flow rate of the fan so as to produce more efficient convection for discharging heat is a key point of current investigation.

Further, referring to FIGS. 1 to 3, a conventional fan assembly includes a fan frame 11 and a fan 12 and the frame wall 111 of the fan frame 11 forms a hollow shell. The hollow shell defines a flow passage 115 with an inlet 112 and an outlet 113 at both lateral sides of the fan frame 11. A hub seat 114 is provided in the flow passage 115 and the fan 12 has a hub 121 and fan blades 122 extending outward in a radial direction from circumference of the hub 121. The fan is rotationally attached to the hub seat 114 so that the fan blades 122 can draw fluid to enter the fan from the inlet 112 and flow out from the outlet 113 via the passage 115.

However, the fluid drew by the fan blades 122 and entering the flow passage 115 is very limited and radial pressure makes the fluid to hit the frame wall 111 and produce noise.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a fan assembly in which a fan frame thereof allows the flow rate of the entering fluid to increase substantially.

Another object of the present invention is to provide a fan assembly in which the fan frame thereof can lower the noise generation.

A further object of the present invention is to provide a fan assembly in which a fan frame thereof can prevent the fan from being offended by foreign objects.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood in the following description with reference to accompanying drawings, in which:

FIG. 1 is a disassembled perspective view of a conventional fan assembly;

FIG. 2 is an assembled perspective view of the conventional fan assembly shown in FIG. 1;

FIG. 3 is a sectional view of the conventional fan assembly shown in FIG. 2;

FIG. 4 is a disassembled perspective view of a fan assembly according to the present invention in the first embodiment thereof;

FIG. 5 is an assembled perspective view of the fan assembly shown in FIG. 4;

FIG. 6 is a sectional view of the fan assembly shown in FIG. 5 illustrating operation thereof;

FIG. 7 is a perspective view illustrating another guard device used in the first embodiment of the present invention;

FIG. 8 is a disassembled perspective view of a fan assembly according to the present invention in the second embodiment thereof;

FIG. 9 an assembled perspective view of the fan assembly shown in FIG. 8;

FIG. 10 is a perspective view illustrating another guard device used in the second embodiment of the present invention;

FIG. 11 a disassembled perspective view of a fan assembly according to the present invention in the third embodiment thereof;

FIG. 12 is an assembled perspective view of the fan assembly shown in FIG. 11;

FIG. 13 s a sectional view of the fan assembly shown in FIG. 12 illustrating operation thereof;

FIG. 14 is a perspective view illustrating another guard device used in the third embodiment of the present invention;

FIG. 15 a disassembled perspective view of a fan assembly according to the present invention in the fourth embodiment thereof;

FIG. 16 is an assembled perspective view of the fan assembly shown in FIG. 15; and

FIG. 17 is a perspective view illustrating another guard device used in the fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 4 and 5, a fan assembly according to the present invention in the first embodiment thereof at least includes a shielding 23 and a guard device 24 and a fan 21. The shielding device 23 and the guard device 24 are mounted to the fan 21 so as to rotationally be joined to a radiator 22. The fan 21 further includes a hub 211 and a plurality of fan blades 212 extending outward from circumference of the hub 211 in a radial direction respectively. The radiator 22 further includes a shaft body 221 with a cylindrical shape and a plurality of fins 222 extending outward from the shaft body 221. Hence, it makes the radiator 22 to constitute a circular shape. A fan seat 223 is provided on the shaft body 221 for engaging with the fan 21. The shielding device 23 is a circular frame with at least a fixing part 231 and the fixing part 231 can form an inversed hook 2311 to fixedly hook the radiator 22. The guard device 24 is a hard skeleton with multiple surrounding stages being assembled to the shielding device 23 such that several openings 241 are constituted.

When the fan assembly is set up, the shielding device 23 is inserted into the radiator 22 and the inversed hook 2311 of the fixing part 231 fixedly hooks the radiator 22 at the lower side thereof to allow the shielding device 23 enclosing radiator 22 and the guard device 24 can surround the fan 21 over the radiator 22.

Referring to FIG. 6 in company with FIG. 4 again, when the fan 21 rotates to draw fluid, the fluid flows to enter the fan 21 not only via the upper part of the guard device 24 on the shielding device but also via the openings 241 of the guard device 24 toward the radiator at the lower part of the fan assembly. In this way, the incoming flow rate of the fluid can increase and enhance efficiency of heat dissipation. Further, due to the guard device 24 being composed of hard skeleton with several openings 241 instead of the conventional fan frame wall, it can decrease chance of the fluid frictionally hitting the fan frame wall 21 greatly during the fan rotating such that chance of generating noise can be lowered and it is possible to prevent the fan 21 from being offended by foreign objects.

Referring to FIG. 7 in company with FIG. 5 again, a single guard device 25 on the shielding device 23 surrounding the fan 21 can be used instead of the multiple stage type guard device 24.

Referring to FIGS. 8, 9 and 10, the second embodiment of the present invention is illustrated. A fan seat 333 is held by support structure 332, which is connected to a shielding device 33. When the shielding device 33 covers a radiator 32, the fan 31 can be arranged on the radiator 32.

Referring to FIGS. 11 to 14, the third embodiment of the present invention is illustrated. A radiator 42 has a shape of cube with a cubic shielding device 43 and the shielding device 43 at least has a fixing part 431. The fixing part 431 is a hole for being passed through by a fastener 47 to engage with the radiator 42 such that the shielding device 43 can be attached to the radiator 42.

Referring to FIGS. 15 to 17, the fourth embodiment of the present invention is illustrated. The fourth embodiment is similar to the third embodiment with a difference from the third embodiment in that a fan seat 533 is held by support structure 532, which is connected to a shielding device 53. When the shielding device 53 covers a radiator 52, the fan 51 can be arranged on the radiator 52.

It is noted that the shielding device 23, 33, 43, 53 and the guard device 24, 25, 34, 35, 44, 45, 54, 55 shown in FIGS. 4 to 17 can be formed with an integral piece instead of being assembled together.

In addition, the guard device 24, 25, 34, 44, 45, 54, 55 can be made of plastics instead of metal.

While the invention has been described with reference to preferred embodiments, it is to be understood that modifications and variations may be easily made without departing from the spirit of this invention defined by the appended claim. 

1. A fan assembly, comprising: a radiator; a fan, being disposed on the radiator; at least a shielding device, having at least a fixing part for being attached to the radiator; and at least a guard device, being disposed on the shielding device, being formed with hard skeleton with a plurality of openings and surrounding the fan for being passed through with fluid; whereby, the openings of the guard device can increase flow rate of the fluid entering the radiator, decrease noise and prevent the fan from being offended by foreign objects.
 2. The fan assembly as defined in claim 1, wherein the guard device is provided with multiple sections in a surrounding way on the shielding device.
 3. The fan assembly as defined in claim 1, wherein the guard device is provided with an integral piece in a surrounding way on the shielding device.
 4. The fan assembly as defined in claim 1, wherein the guard device is made of metal.
 5. The fan assembly as defined in claim 1, wherein the guard device is made of plastics.
 6. The fan assembly as defined in claim 1, wherein the shielding device is a circular frame body.
 7. The fan assembly as defined in claim 1, wherein the shielding device is a square frame body.
 8. The fan assembly as defined in claim 1, wherein the shielding device and the guard device are formed as a single piece. 